Process for preparing functionalized polyorganosiloxane resins by redistribution in the presence of triflic acid and/or of at least one derivative thereof and of a nonbasic inert filler

ABSTRACT

The invention provides a method for preparing functionalized polyorganosiloxane resins (POS) comprising units M: (R 3 SiO 1/2 ), Q: (SiO 4/2 ) and M′: (Y a R 3-a SiO 1/2 ) and optionally D: (R 2 SiO 2/2 ) and/or D′: (RYSiO 2/2 ) and T: (RSiO 3/2 ) and/or T′: (YSiO 3/2 ), wherein in said units R is C 1 -C 10  alkyl or C 8 -C 12  aryl and Y is a functional group (such as Si—H), by redistributing POS resins, using POSf bearing functional groups M′ and/or D′ and/or in the presence of an acid catalyst such as triflic acid or one of its derivatives and a non-basic inert filler: carbon black, diatomaceous earth, zeolite or acid or neutral oxide (Al 2 O 3 , Na 2 O, TiO 2 , MgO, silica). The invention also provides said catalyst system.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.10/509,060, filed Jun. 17, 2005, now allowed, which is the U.S. nationalstage of International Application No. PCT/FR03/00888, filed Mar. 20,2003, and claims priority under 35 U.S.C. § 119 (a)-(d) of French PatentApplication No. 02/03769, filed Mar. 26, 2002, said applications beingincorporated by reference herein in their entireties and relied upon.

Reference is also made to commonly assigned application Ser. No.10/509,071 (Attorney Docket No. 0070681-000015), which is the U.S.national stage of International Appln. No. PCT/FR03/00889, filed Mar.20, 2003, and which was concurrently filed with parent application Ser.No. 10/509,060 on Jun. 17, 2005, as well as its continuation applicationSer. No. ______ (Attorney Docket No. 0070681-000099) concurrently filedherewith.

The field of the invention is that of the production of silicone orpolyorganosiloxane resins, referred to hereinbelow as POS resins. ThePOS resins more especially targeted are those comprising siloxyl unitsM: (R₃SiO_(1/2)) and optionally D: (R₂SiO_(2/2)) and/or T: (RSiO_(3/2)),said resins moreover being functionalized, i.e. they comprise units M′:(Y_(a)R_(3-a)SiO_(1/2)) and optionally D′: (RYSiO_(2/2)) and/or T:(YSiO_(3/2)); Y representing in these formulae a functional group, forexample a hydrogen or a vinyl, R a hydrocarbon-based group and a=1 or 2.

These functional silicone resins MQ may be liquid or solid at roomtemperature. They have been known for a very long time and are currentlyused in many applications, for instance in electrical insulatingvarnishes, heat-resistant coatings, encapsulating materials forsemiconductor components, etc.

The functional MQ POS resins (MM′Q) whose production forms the subjectof the present invention may also comprise siloxyl units D and/or T, oreven functionalized siloxyl units D′ and/or T′.

The main routes of access to functional MQ resins are currentlyprocesses of condensation/hydrolysis starting with sodium silicate oralkyl silicate (U.S. Pat. No. 2,676,182, U.S. Pat. No. 2,814,601, U.S.Pat. No. 2,857,356, U.S. Pat. No. 4,707,531). These techniques are notwithout drawbacks, especially in terms of ease of use, cost andproduction of ecotoxic and/or hazardous effluents.

However, an alternative, which is attractive in principle, to thesecondensation/hydrolysis techniques exists, namely the redistribution ofPOS oils in a POS resin comprising MQ units.

By way of illustration of this route of functionalization of resins ofMQ type by redistribution, mention may be made of U.S. Pat. No.4,774,310, U.S. Pat. No. 5,494,979 (≈EP-A-0 617 094) and U.S. Pat. No.5,510,430.

Patent U.S. Pat. No. 4,774,310 describes the preparation of Si—Hfunctionalized resins by redistribution of tetramethyldisiloxane (M′₂)in an MQ resin dissolved in an organic solvent, in the presence oftriflic acid or perfluoroalkanesulfonic acid (TFOH). The reaction mediumis heated to a temperature of between 50 and 100° C. and the triflicacid catalyst is then neutralized with NaHCO₃. The MM′Q resins thusobtained may react with organic or organosiloxane substances bearingolefin unsaturation (column 2, line 66 to column 3, line 3). Said patentalso makes a vague and general allusion to supported acid catalysts(column 2, line 18).

Patent U.S. Pat. No. 5,494,979 (≈EP-A-0 617 094) discloses thepreparation of MQ resins functionalized with acrylate radicals, byredistribution of polydiorganosiloxane oils bearing units D and unitsD^(acrylate):MD^(acrylate) _(x)D_(y)M. This redistribution is performedusing a xylene solution of commercial MQ resin, using triflic acid aspreferred acid catalyst. The POS MD^(acrylate) _(x)D_(y)M used is asdescribed in example 2 of German patent 3 810 140. This preparation ofacrylate-functionalized MQ resins also includes steps of neutralization,for example with sodium carbonate, and then of removal of the solidresidues by filtration.

American patent U.S. Pat. No. 5,510,430 concerns the functionalizationof resins of MQ type with a whole range of functional groups, forexample aryl, alkyl, vinyl or Si—H. The functionalization process usedis based on the redistribution of disiloxanes and chlorosilanes. Theexamples more specifically disclose the redistribution of MQ resins offormula: [(CH₃)₃SiO_(1/2)]_(0.65)[SiO_(4/2)]₁ dissolved in toluene, byplacing in contact with tetramethyldisiloxane and an acid catalyst thatmay be a phosphonitrile chloride, a linear phosphazene or triflic acid(example 6). This is therefore a redistribution MQ+M′₂ at the refluxtemperature of the solvent, with quenching of the reaction by usingmethanol, resulting in precipitation. Filtration and washing steps arethen performed.

It emerges from this review of the prior art that the redistribution ofMQ resins using functional oligo-organosiloxanes or functionalpolyorganosiloxanes, in the presence of triflic acid, does not makereference to the use of any cocatalyst, and in any case does not at allmention the use of an inert filler such as carbon black in combinationwith triflic acid.

Moreover, it would be entirely desirable to improve the known processes,especially in terms of functionalization yields and degrees ofconversion of the POSs used for functionalization (M′₂).

Under these circumstances, one of the essential objects of the presentinvention is to provide an improved process for functionalizing siliconeresins comprising siloxyl units M and Q, by redistribution using POSsbearing functional units or units for functionalization; this improvedprocess needing to afford improvements in terms of ease of use,significant increase in the degree of functionalization of theredistributed resin and also of the degree of conversion of thefunctional POS reagents, while at the same time keeping the cost of theprocess as low as possible.

Another essential objective of the invention is to provide a new acidiccatalytic system, based on triflic acid or a derivative, which is usefulor for the functionalization of silicone resins comprising units M andQ, by redistribution, using a redistribution reagent consisting of a POSbearing functional units or units for functionalization, said catalyticsystem having properties such that it allows an improvement in theredistribution kinetics and also in the yield and degree of conversionof the reaction, and does so without entailing any methodologycomplications or prohibitive cost increases.

Another essential objective of the invention is to significantly improvethe homogeneous or heterogeneous catalysis of the reactions forfunctionalization of resins comprising siloxyl units M and Q byredistribution, using POSs bearing functional units or units forfunctionalization. The targeted improvement should be reflected in termsof the control, reliability and production efficiency of thecorresponding industrial processes.

Another objective targeted through the improvement of the catalyticsystem is that of improving the quality of the functionalized MQ resinsobtained, while at the same time optimizing the safety and minimizingthe ecotoxic impact of the industrial processes under consideration.

Another essential objective of the invention is to provide a process forthe functionalization of silicone resins MQ by redistribution, in whichthe yield of incorporation of the POS for functionalization (M′₂) issignificantly increased relative to those obtained by the knownprocesses.

Another essential objective of the invention is to provide a process forthe functionalization of silicone resins MQ by redistribution using POSfor functionalization, which process offers the possibility ofcontrolling the content of functionalities introduced and also thelocation of these functions on the resin.

Another essential objective of the invention is to propose a process forthe functionalization of silicone resins of MQ type by redistribution,this process being able to be applied to a wide variety of chemicalfunctions, so as to be able to produce a large variety of functional MQresins adapted to a host of applications, from a starting materialconsisting of a resin core on the periphery of which are placed selectedchemical functions.

These objectives, among others, are achieved by the present invention,which relates firstly to a process for preparing functionalizedpolyorganosiloxane (POS) resins comprising units M: (R₃SiO_(1/2)), Q:(SiO_(4/2)) and M′: (Y_(a)R_(3-a)SiO_(1/2)) and optionally D:(R₂SiO_(2/2)) and/or D′: (RYSiO_(2/2)) and T: (RSiO_(3/2)) and/or T′:(YSiO_(3/2)) with, in these units:

-   -   the radicals R, which may be identical or different,        representing a C₁-C₁₀ alkyl or a C₈-C₁₂ aryl,    -   the radicals Y being identical or different and representing a        functional group Y,        by redistribution of POS resins using POSf bearing functional        units M′ and/or D′ and/or T′, as defined above, in the presence        of an acid catalyst, said process being characterized:    -   in that at least one catalyst is used of formula (I) below:

(C_(m)F_(2m+1)SO₂)_(n)A  (I)

-   -    in which:        -   m is an integer greater than or equal to 1;        -   n is an integer equal to 1 or 2 and A represents OH, NH₂ or            NH or CH₂ with:        -   (i) n=1 and A=OH or        -   (ii) n=1 and A=NH₂ or NHR with R being a radical of SO₂-Z            type with Z being a group other than C_(m)F_(2m+1)        -   (iii) n=2 and A=NH;        -   it is necessary for the acid catalyst to be liquid under the            working conditions.

Furthermore, the choice of the catalyst may be guided by the gas-phaseacidity scale described by I. Koppel et al., J. Am. Chem. Soc., 116(1994) 3047. Thus, the acids used should be those whose acidity measuredin the gas phase is greater than that of sulfuric acid, thus, in termsof ΔG<302 Kcal/mol. For example, (CF₃SO₂)₂NH ΔG=292 Kcal/mol,(C₄F₉SO₂)₂NH ΔG=284 Kcal/mol;

-   -   and in that this catalyst is in the presence of a nonbasic inert        filler.

The term “nonbasic” means more specifically and for example, for thepurposes of the present invention, an inert filler that is incapable ofreacting with the acid catalyst to neutralize it and make it“catalytically” less active or even inactive.

It is thus seen that one of the essential constituent means of theinvention concerns the catalytic system formed by a combination oftriflic acid or a derivative thereof with a nonbasic filler (or inertsupport).

Preferably, the nonbasic inert filler is chosen from the group ofproducts comprising: carbon black, an acidic or neutral oxide, andmixtures thereof.

Even more preferably, the acidic or neutral oxide is selected from thegroup comprising: Al₂O₃, Na₂O, TiO₂, MgO, neutral or acidic zeolites,silica, and mixtures thereof.

The use of this catalytic system makes it possible to obtain yields forincorporation of POSs bearing functional units (for example M′₂) ofgreater than 50%, preferably 60% and even more preferably 70%, to becompared with yields obtained in the processes according to the priorart having an upper limit of 30%.

The performance qualities obtained by virtue of this combination oftriflic acid or derivative/non-basic inert filler are entirelysurprising and unexpected, not only in terms of yield of incorporationof POSf, but also as regards the degree of functionalization, i.e. thecontent of Si-function units in the resin MQ. Specifically, this degreeis greater than 2.5% by weight and preferably greater than 3% in termsof the redistribution.

Moreover, the specifications of reduced cost, ease of use, safety andlimited or even zero ecotoxicity are largely satisfied by the processaccording to the invention.

The catalytic system according to the invention is also noteworthy interms of kinetics.

Furthermore, the redistribution may be readily stopped by neutralizationof the acid catalyst using a base (for example NaHCO₃, Na₂CO₃, CaCO₃)and/or by deactivation by heat and/or by adsorption (carbon black,diatomaceous earth, etc.).

The neutralization is all the more simple since the residual acidity inthis case is markedly lower than that obtained after conventionalredistribution catalysis. In addition, the neutralization has theadvantage that the final reaction medium is not corrosive toward thefunctionalized MQ silicone resins. The stability of these resins withrespect to temperature and storage is thereby greater.

Still regarding this stability aspect of the redistributed resin, it mayalso be pointed out that, since the catalytic system is present in traceamount in the reaction medium, it is nondegrading with respect to theproducts used and/or the products obtained after redistribution.

This process also makes it possible to control the degree offunctionalization of the MQ resin, or even the location of its functionson the resin. Thus, starting with an MQ resin core, for convenience, itis possible to construct around this core a functional peripheralstructure, by customizing the morphology and hydrodynamic volume of theresin. For example, it may be envisaged to produce on the core hair madeof POS segments of (D)_(x) type.

The functions that may be incorporated into the resin are, for example,of Si—H, Si-Vi, Si-phenyl, Si-alkyl, Si-alkenyl, Si-alkyne, Si-alkylhalide, Si-alkyl epoxide, Si-alkyl-polyether, Si-carbinol,Si-alkylammonium, Si-alkylcarboxylic acid or Si-alkylthiol type. It maythus be hoped to be able to provide functional resins adapted to a hostof applications.

In point of fact, it may be envisaged to provide a tree produced from anindustrial MQ-based resin.

Thus, the functions provided by the POSf are such that Y isadvantageously chosen from the group comprising:

-   -   hydrogen    -   an alkenyl    -   an alkynyl    -   an aryl (preferably a phenyl)    -   an (alkyl)epoxy    -   an ether or a polyether    -   a carboxylic acid    -   an amide    -   an amine    -   a halide    -   an alcohol    -   a thiol or any other sulfur derivative.

In accordance with the invention, the starting MQ resins may be eitherunfunctionalized or already functionalized.

As regards the unfunctionalized MQ resins, they are commercial products,for example of formula (M_(x)Q_(y))_(z) with x between 0.5 and 1 and ybetween 0 and 1.

The already-functionalized MQ resins are especially those obtained bythe process in accordance with the present invention fromunfunctionalized starting MQ resins or by the synthetic process startingwith sodium silicate described in patent U.S. Pat. No. 2,676,182.

Advantageously, the starting MQ resin is in the form of a solution in anorganic solvent, for instance xylene or toluene, or as a solution in thePoSf oil for functionalization.

As regards the nonbasic inert filler, it is a fine powder, i.e. theparticle size of which is such that the grains are between 0.001 and 300μm.

It is, for example, Al₂O₃, Na₂O, TiO₂, MgO, zeolite, silica,diatomaceous earth or carbon black (the latter filler being preferred),which is in the form of powder, granules or any other molded form. Inpractice, powdered carbon black is dispersed into the PoSf oil forfunctionalization.

As specifically regards these POSfs bearing functional units M′ and/orD′ and/or T′, which are useful for the redistribution, it will bepreferred to use those of formula (IV.1) or (IV.2) below:

in which:

-   -   Y and R are as defined above,    -   a and b=0 to 2,    -   0≦x≦200 and preferably 0≦x≦50,    -   0≦y≦200 and preferably 0≦y≦50,    -   with the condition that if x+y=0, then a and/or b≠0,    -   1≦x′≦10 and preferably 1≦x′≦8,    -   0≦y′≦10 and preferably 0≦y′≦3,    -   3≦x′+y′≦10 and preferably x′+y′=3, 4 or 5.

The POSfs of formulae (IV.1), (IV.2) and (IV.3) correspond,respectively, to disiloxanes, linear polyorganosiloxanes and cyclicoligoorganosiloxanes.

These POSfs are, for example, M₂, M₂ ^(Vi), MD_(x)M, MD_(x)D′_(y)M,M′D_(x)D′_(y)M′, MD_(x)D^(Vi) _(y)M, M^(Vi)D_(x)D^(Vi) _(y)M^(Vi),M′D_(x)M′, M^(Vi)D_(x)M^(Vi).

It should be noted, as regards the acid catalyst of formula (I)(i)(ii)or (iii) that the fluoro chain C_(m)F_(2m+1) may be extended so as toincrease the acidity of the catalyst and subsequently its efficacy.

In practice, the acid catalysts may be, for example:

-   -   (i) n=1 and A=OH    -   (ii) n=1 and A=NH₂ or NHR with R being a radical of SO₂-Z type        with Z being a group other than C_(m)F_(2m+1)    -   (iii) n=2 and A=NH.

In the preferred embodiment of the process according to the invention,the catalyst is triflic acid of formula (I)(i) with m=1 and/or thetrifluoromethanesulfonimide acid of formula (I)(iii) with m=1.

In quantitative terms, it may be pointed out that the concentration ofacid catalyst (I) is advantageously between 1 ppm and 2% relative to thestarting resin. Moreover, the catalyst (I)/inert support (preferablycarbon black) mass ratio is preferably between 0.1 and 10, and ispreferably of the order of 1.

In accordance with the invention and according to one preferredembodiment, the nonbasic inert filler is not linked to the acid catalyst(I) (triflic acid or derivatives). They cohabit separately of each otherin the reaction medium.

The catalyst may be homogeneous or heterogeneous. It is preferablyhomogeneous, the catalyst being in this case dissolved in the reactionmedium.

According to a first variant of heterogeneous catalysis, the nonbasicinert filler may be an inert support onto which the catalyst is at leastpartially absorbed or is intended to be at least partially absorbed.

According to a second variant of heterogeneous catalysis, the catalystis at least partially absorbed onto an inert support other than thenonbasic inert filler, this filler being moreover present in thereaction medium. It is necessary for the acid catalyst to be liquidunder the working conditions. However, it may be solid at 25° C. andmolten at the reaction temperature.

The third variant of heterogeneous catalysis corresponds to acombination of the first and second variants.

The process according to the invention may be defined by othermethodological characteristics, and in particular in that it comprisesthe following essential steps:

-   -   1—combining the starting POS resin, the POSf bearing functional        units, the acid catalyst (I) and the nonbasic inert filler        (Al₂O₃, Na₂O, TiO₂, MgO, silica, diatomaceous earth, zeolite or        carbon black, the latter filler being preferred), in an organic        solvent;    -   2—reacting preferably at a temperature θr greater than or equal        to room temperature and less than or equal to the boiling point        of the solvent, and even more preferably between 50° C. and 100°        C.;    -   3—optionally quenching the reaction by adding an agent for        neutralizing the acid catalyst (I);    -   4—removing the inert filler (advantageously the carbon black)        from the reaction medium, preferably by filtration.

Advantageously, as has already been mentioned above, the organicsolvent, preferably xylene, toluene or white spirit, is provided in thereaction medium by means of a solution of starting POS resin (MQ) insaid solvent. It is also possible to work with an excess offunctionalized silicone oil.

According to another advantageous embodiment, the nonbasic inert filler,preferably the carbon black, is in the form of powder dispersed in thePoSf bearing functional units.

The process of functionalization by redistribution according to theinvention makes it possible especially to graft Si—H and/or Si-alkenyl(preferably vinyl) units onto MQ resins. Given that these functions H oralkenyl are reactive functions, among others, it may be envisaged, inaccordance with the invention, to perform a second functionalizationaccording to a hydrosilylation mechanism, so as to covalently attach asecond functional segment onto the already functionalized MQ resin.

This corresponds to the case in which Y represents H or alkenyl in thefunctional units M′ and/or D′ and/or T′, of the POSf. In this variant,after the redistribution, other functionalization radicals Y₁ bearing atleast one unsaturation (preferably ethylenic) or at least one Si—H unitare grafted onto the ≡Si—H or ≡Si-alkenyl units, respectively, of theredistributed resin.

As regards the methodology, it may also be pointed out that it ispreferable, in order for the redistribution to proceed correctly, forthe reaction atmosphere to be free of moisture. Thus, the process isadvantageously performed under an atmosphere of neutral gas, for exampleargon or nitrogen.

The reaction pressure is advantageously normal and the reactiontemperature may range from room temperature (for example 25° C.) to atemperature of 150° C. or more.

The redistribution is stopped by means of deactivating the catalyst.Since it is an acid catalyst, in this instance triflic acid orderivatives thereof, the deactivation may be performed using a basicneutralizer, for instance sodium carbonate Na₂CO₃ or sodium bicarbonateNaHCO₃.

The neutralization is all the more necessary when the catalysis ishomogeneous catalysis, since, in such a case, in contrast toheterogeneous catalysis, the catalyst is not removed at the end of thereaction.

According to one variant of the process in accordance with theinvention, the redistributed and functionalized resin obtained issubjected to at least one other redistribution/functionalization, usingPOS bearing functional units.

The invention also relates to a catalytic system that is useful forpreparing functionalized polyorganosiloxane (POS) resins comprisingunits M: (R₃SiO_(1/2)), Q: (SiO_(4/2)) and M′: (Y_(a)R_(3-a)SiO_(1/2))and optionally D: (R₂SiO_(2/2)) and/or D′: (RYSiO_(2/2)) and/or T:(RSiO_(3/2)) and/or T′: (YSiO_(3/2)) with, in these units:

-   -   the radicals R being identical or different and representing a        C₁-C₁₀ alkyl or a C₈-C₁₂ aryl;    -   the radicals Y being identical or different and representing a        functional group Y, preferably chosen from the group comprising:        -   hydrogen        -   an alkenyl        -   an alkynyl        -   an aryl (preferably a phenyl)        -   an (alkyl)epoxy        -   an ether or a polyether        -   a carboxylic acid        -   an amide        -   an amine        -   a halide        -   an alcohol        -   a thiol or any other sulfur derivative            by redistribution of POS resins using POSs bearing            functional units M′ and/or D′ and/or T′ as defined above,            characterized in that it comprises:    -   A—at least one catalyst of formula (I) below:

(C_(m)F_(2m+1)SO₂)_(n)A  (I)

-   -    in which:        -   m is an integer greater than or equal to 1;        -   n is an integer equal to 1 or 2 and A represents OH, NH₂ or            NH with:            -   (i) n=1 and A=OH            -   (ii) n=1 and A=NH₂ or NHR with R being a radical of                SO₂-Z type with Z being a group other than C_(m)F_(2m+1)            -   (iii) n=2 and A=NH;    -   B—and at least one nonbasic inert filler preferably chosen from        the group of products comprising: carbon black, an acidic or        neutral oxide (preferably selected from the group comprising:        Al₂O₃, Na₂O, TiO₂, MgO, zeolite, silica, diatomaceous earth,        carbon black, and mixtures thereof), and mixtures thereof.

This catalytic system is markedly more efficient than the conventionalcatalysts for the redistribution of silicone resins MQ using only TFOHor TFSI. In terms of kinetics, conversion and yield, it makes itpossible to obtain high-quality functionalized MQ resins, thefunctionality of which is controlled and adapted to the intended use.These performance qualities are all the more advantageous since they areobtained without sacrificing the imperatives of cost, safety, absence ofecotoxicity and ease of use.

The examples that follow will make it possible to understand moreclearly the process and the catalyst according to the invention, byhighlighting all their advantages and the possible implementationvariants.

EXAMPLES I Comparative Example Tonsil Catalyst

500 g of a xylene solution containing 300 g of resin (M_(x)Q_(y))_(z)(structure determined by ²⁹Si NMR:(M_(0.88)M′_(0.06)D*_(0.05)Q₁*)_(z)−M/Q=0.9) are introduced into a 1liter reactor under nitrogen. 30 g of M′₂ (1.49 mol SiH/kg of resin) and2.7 g of Tonsil are added. The mixture is brought to 70° C. and heatedat this temperature for 7 hours. After cooling to room temperature, thereaction mass is filtered through cardboard and then through a 0.45 μmPTFE filter to remove the Tonsil. During the test, several samples aretaken and make it possible to monitor the amount of SiH bound to theresin and also the nature and relative proportions of the lightfractions in the reaction medium as a function of the reaction time.

TABLE 1 Reaction time 0 h 1 h 3 h 6 h 7 h Amount of SiH on the resin 0%0.8% 1.2% 1.47% 1.39% (quantification by IR) Conversion of M′₂ 0%  52% 74%   78%   82% (quantification by GC)Final structure of the resin (²⁹Si NMR):(M_(0.82)M′_(0.08)D*_(0.05)Q*)_(z)Final yield of incorporation of SiH: 32%.

II Comparative Example H₂SO₄+Black Catalyst

The operating conditions are the same as those described in example I.

Materials added: 491.26 g of xylene solution, i.e.

-   -   304.6 g of resin    -   30.1 g of M′₂, i.e. 1.44 mol/kg of resin    -   0.44 g of H₂SO₄    -   0.60 g of Black 4S        Reaction time: 7 hours        Monitoring of the reaction:

TABLE 2 Reaction time 0 h 1 h 3 h 6 h 7 h Amount of SiH on the 0% 0.38%0.73% 0.89% 1.00% resin (quantification by IR) Conversion of M′₂ (%) 0%  33% 58.5%   68%   70% (quantification by GC)Final structure of the resin (²⁹Si NMR): M_(0.79)M′_(0.03)D*_(0.06)Q*Final yield of incorporation of SiH: 25%.

III Example CF₃SO₃H Catalyst

The operating conditions are the same as those described in example I.

Materials added: 500.0 g of xylene solution, i.e.

-   -   300 g of resin    -   30.0 g of M′₂, i.e. 1.47 mol/kg    -   1.31 g of CF₃SO₃H        Reaction time: 7 hours        Monitoring of the reaction:

TABLE 3 Reaction time 0 h 1 h 3 h 6 h 7 h Amount of SiH on the 0% 2.79%3.17% 3.08% 3.28% resin (quantification 3.37% by KOH assay) (IR)Conversion of M′₂ (%) 0% 94.5%   97%   97%   97% (quantification by GC)Final structure of the resin (²⁹Si NMR):(M_(0.72)M′_(0.11)D*_(0.04)Q*)_(z)Final yield of incorporation of SiH: 75%.

IV Example CF₃SO₃H+Black 4S Catalyst

The operating conditions are the same as those described in example I.

Materials added: 490.8 g of xylene solution, i.e.

-   -   304.3 g of resin    -   30.1 g of M′₂, i.e. 1.49 mol/kg    -   1.28 g of CF₃SO₃H    -   1.83 g of Black 4S        Reaction time: 7 hours        Monitoring of the reaction:

TABLE 4 Reaction time 0 h 1 h 3 h 6 h 7 h Amount of SiH on the 0% 1.79%3.05% 3.14% 3.18% resin (quantification 3.05% by KOH assay) (IR)Conversion of M′₂ (%) 0%   81%   96%   97%   97% (quantification by GC)Final structure of the resin (²⁹Si NMR)(M_(0.72)M′_(0.14)D*_(0.05)Q*)_(z)Final yield of incorporation of SiH: 73%.

V Comparative Test Tonsil Catalyst

-   -   500 g of a xylene solution containing 300 g of resin        (M_(x)Q_(y))_(z) (NMR analyses: M_(0.9)D_(0.02)Q₁ with M/Q=0.9        (molar)) are introduced into a 3 liter reactor under nitrogen.        This solution is brought to 70° C. and 30 g (1.49 mol SiH/kg of        resin) of M′₂ and 2 g of Tonsil are added. The mixture is left        to react for 7 hours at 70° C. The reaction mass is cooled and        filtered through cardboard+0.45 μm PTFE filter to remove the        Tonsil. During this test, a certain number of samples are taken,        which make it possible to monitor the amount of SiH units as a        function of time:        T=0: 0%, T=1 h: 0.8%, T=3 h: 1.2%, T=7 h: 1.47%, or 1.39% (IR),        i.e. 0.48 mol SiH/kg of resin.

The yield for incorporation of the SiH units is 32%. The NMR analysesshow that the structure of the final resin is:(M_(0.8)M′_(0.07)D*_(0.04)Q₁)_(z).

VI H₂SO₄ Black Catalysis Test

Same operating conditions as for example I:

-   -   500 g of xylene solution containing 300 g of resin        (M_(x)Q_(y))_(z)    -   30 g of M′₂, i.e. 1.49 mol of SiH/kg of resin    -   1.09 g of H₂SO₄    -   1.39 g of Black 2S        reaction time: 8 hours        SiH IR assay: 1.24%, i.e. 0.43 mol SiH/kg of resin        yield of SiH incorporation: 29%        final resin structure: (M_(0.8)M′_(0.05)D*_(0.08)Q₁)_(z)

VII CF₃SO₃H Catalysis Test

Same operating conditions as for example I:

-   -   642.1 g of xylene solution containing 400 g of resin        (M_(x)Q_(y))_(z)    -   47.21 g of M^(Vi) ₂, i.e. 1.27 mol of Si-vinyl/kg of resin    -   2.45 g of carbon black    -   1.71 g of CF₃SO₃H        reaction time: 8 hours 10 minutes        IR assay: 1.1 mol Si-vinyl/kg of resin        yield of SiH incorporation: 87%        final resin structure: (M_(0.76)M^(Vi) _(0.11)D*_(0.03)Q₁)_(z).

1. A process for preparing functionalized polyorganosiloxane (POS)resins comprising units M: (R₃SiO_(1/2)), Q: (SiO_(4/2)) and M′:(Y_(a)R_(3-a)SiO_(1/2)) and optionally D: (R₂SiO_(2/2)) and/or D′:(RYSiO_(2/2)) and T: (RSiO_(3/2)) and/or T′: (YSiO_(3/2)), wherein: theradicals R, which are identical or different, represent C₁-C₁₀ alkyl orC₈-C₁₂ aryl; and the radicals Y, which are identical or different,represent a functional group Y selected from the group consisting ofhydrogen, alkenyl, alkynyl, aryl, (alkyl)epoxy, ether, polyether,carboxylic acid, amide, amine, halide, alcohol, thiol and other sulfurderivative; said process comprising conducting a redistribution reactionbetween a POS resin and a POSf compound bearing functional units M′and/or D′ and/or T′, as defined above, in the presence of an acidcatalyst, wherein: at least one catalyst has formula (I) below:(C_(m)F_(2m+1)SO₂)_(n)A  (I) wherein: m is an integer greater than orequal to 1; n is an integer equal to 1 or 2 and A represents OH, NH₂ orNH with: (i) n=1 and A=OH; or (ii) n=1 and A=NH₂ or NHR with R being aradical of SO₂-Z type, with Z being a group other than C_(m)F_(2m+1); or(iii) n=2 and A=NH; and wherein said catalyst is in the presence of anonbasic inert filler.
 2. The process as claimed in claim 1, wherein thenonbasic inert filler is carbon black, a diatomaceous earth, or anacidic or neutral oxide, or a mixture thereof.
 3. The process as claimedin claim 1, wherein the acidic or neutral oxide is Al₂O₃, Na₂O, TiO₂,MgO, silica or zeolite, or a mixture thereof.
 4. The process as claimedin claim 1, wherein Y is phenyl.
 5. The process as claimed in claim 1,wherein the catalyst is triflic acid (TFOH) of formula (I) (i) with m=1and/or the trifluoromethanesulfonimide acid (TFSI) of formula (I) (iii)with m=1.
 6. The process as claimed in claim 2, wherein the catalyst istriflic acid (TFOH) of formula (I) (i) with m=1 and/or thetrifluoromethanesulfonimide acid (TFSI) of formula (I) (iii) with m=1.7. The process as claimed in claim 1, wherein the catalyst is supportedon the nonbasic inert filler, wherein the concentration of acid catalyst(I) is between 1 ppm and 2% by weight relative to the starting resin andwherein the catalyst (I)/inert filler support mass ratio is between 0.1and
 10. 8. The process as claimed in claim 7, wherein the inert fillersupport is carbon black.
 9. The process as claimed in claim 7, whereinthe catalyst (I)/inert filler support mass ratio is of the order of 1.10. The process as claimed in claim 9, wherein the inert filler supportis carbon black.
 11. The process as claimed in claim 7, wherein thecatalyst is triflic acid (TFOH) of formula (I) (i) with m=1 and/or thetrifluoromethanesulfonimide acid (TFSI) of formula (I) (iii) with m=1.12. The process as claimed in claim 11, wherein the inert filler supportis carbon black.
 13. The process as claimed in claim 1, comprising thefollowing essential steps: (1) combining the starting POS resin, thePOSf bearing functional units, the acid catalyst (1) and the nonbasicinert filler in an organic solvent; (2) reacting at a temperature θrgreater than or equal to room temperature and less than or equal to theboiling point of the solvent; (3) optionally quenching the reaction byadding an agent for neutralizing the acid catalyst (I); and (4) removingthe inert filler from the reaction medium.
 14. The process as claimed inclaim 13, wherein the inert filler comprises carbon black, and/orwherein the reaction temperature is between 50° C. and 100° C., and/orwherein the inert filler is removed from the reaction medium byfiltration.
 15. The process as claimed in claim 13, wherein the acidcatalyst is triflic acid (TFOH) of formula (I) (i) with m=1 and/or thetrifluoromethanesulfonimide acid (TFSI) of formula (I) (iii) with m=1.16. The process as claimed in claim 15, wherein the inert fillercomprises carbon black, and/or wherein the reaction temperature isbetween 50° C. and 100° C., and/or wherein the inert filler is removedfrom the reaction medium by filtration.
 17. The process as claimed inclaim 13, wherein the organic solvent is provided in the reaction mediumby means of a solution of starting POS resin in said solvent, andwherein the nonbasic inert filler is in the form of powder dispersed inthe POSf bearing functional units.
 18. The process as claimed in claim13, wherein the organic solvent is xylene or toluene, and/or wherein thenonbasic inert filler is carbon black.
 19. The process as claimed inclaim 1, wherein Y═H or alkenyl in the functional units M′ and/or D′and/or T′ of the POSf, and wherein, after the redistribution, otherfunctionalization radicals Y₁ bearing at least one unsaturation or atleast one Si—H unit are grafted by hydrosilylation onto the ≡Si—H or—Si-alkenyl units, respectively, of the redistributed resin.
 20. Theprocess as claimed in claim 19, wherein other functionalization radicalsY₁ bearing at least one ethylenic unsaturation are grafted byhydrosilylation onto the ≡Si—H or ≡Si-alkenyl units, respectively, ofthe redistributed resin.
 21. The process as claimed in claim 13, whereinY═H or alkenyl in the functional units M′ and/or D′ and/or T′ of thePOSf, and wherein, after the redistribution, other functionalizationradicals Y₁ bearing at least one unsaturation or at least one Si—H unitare grafted by hydrosilylation onto the ≡Si—H or ≡Si-alkenyl units,respectively, of the redistributed resin.
 22. The process as claimed inclaim 21, wherein other functionalization radicals Y₁ bearing at leastone ethylenic unsaturation are grafted by hydrosilylation onto the ≡Si—Hor ≡Si-alkenyl units, respectively, of the redistributed resin.